Pierre Ganty Jean-François Raskin Laurent Van Begin From Many Places to Few: Automatic Abstraction Refinement for Petri Nets. 124-143 2007 conf/apn/2007 ICATPN http://dx.doi.org/10.1007/978-3-540-73094-1_10 db/conf/apn/icatpn2007.html#GantyRB07